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Pest fish profiles
Tilapia Mariae – Spotted Tilapia
Overview
Detailed
information
Synonyms
Classification
Appearance
Size
Natural & introduced distrubition
Diet
Reproduction
Ecological tolerances
Ecological impacts
Glossary
References
Contact details
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Common names:
Spotted Tilapia. Also known as Black Mangrove Cichlid, Niger
Cichlid or Tiger Cichlid.
Reproduction:
T.mariae Reaches sexual maturity at 10-15cm length. Parents
prepare nest site on logs, leaves and debris. Eggs (300-6000) are
guarded by parents and hatch in 1-3 days. Parents stay around until
fish are free swimming.
Appearance:
Both sexes are similar in size and appearance. Adults have a
strongly compressed and oval-shaped body, with large eyes,
rounded snout and small mouth with thickened lips. Three anal
spines and short, rounded snout. Dark olive green to light yellow
green with 8-9 dark bars (less evident in adults) and 2-6 large dark
spots along middle of side between the bars.
Ecological tolerances:
There is limited published information on the physiological
tolerances of T. mariae. The species is eurythermal with upper and
lower lethal temperatures of 37°C and 11°C respectively, and a
preffered temperature range of 25-33°C (Siemien and Stauffer
1989).
Size:
Maximum size: 30-40cm total length (TL), but can mature and
reproduce at smaller sizes (9-18cm TL).
Ecological impacts:
There is very little information on the ecological impacts of T.
mariae in its introduced range including northern Queensland. The
species is territorial and aggressive during the spawning season
while non-breeding fish are generally non-aggressive and nonterritorial.
Natural and introduced distribution:
It occurs in coastal lagoons from southern Cameroon to the Ivory
Coast, in western equatorial Africa. It has been introduced into
three countries: the former USSR, the USA and Australia.
Habitat:
Inhabits still or flowing waters in rocky or mud-bottom areas, in
both non-tidal and estuarine reaches.
Diet:
Tilapia mariae is primarily a planktivore (feeding on unicell algae),
but is an opportunistic feeder on filamentous alagae, cyanobacteria
(blue-greens), detritus, leafy aquatic plants, invertebrates and fish
eggs. The species has numerous, fine teeth with moveable slender
shafts adapted for rasping and grinding. It has numerous gill rakers
for sifting small food particles and has a long gut (x2.9 its body
length) which is characteristic of a herbivorous (plant) or plankton
feeder.
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Detailed information
Synonyms
Tilapia mariae (Boulenger 1899)
Tilapia mariae mariae (Boulenger 1899)
Tilapia bubia (Lonnberg 1904)
Tilapia mariae dubia (Lonnberg 1904)
Tilapia meeki (Pellegrin 1911)
Classification
Order Perciformes
Suborder Labroidei
Family Cichlidae
Tribe Tilapiini
Genus Tilapia
Species mariae
Appearance
Sexes are similar in size and appearance, though males tend to be
larger with longer dorsal and anal fins. In males, the pelvic fins
extend back to the 1st soft ray of the anal fin, while in females, the
fins barely reach the 1st anal fin spine.
Juvenile colour: olive green with 8-9 well marked, dark vertical
bands and distinct black 'tilapia spot' on rear portion of dorsal fin.
Juvenile:
Adult colour: Sexes are similar in colour: dark olive green to
yellowish green or grey with a pink flush on the throat during the
breeding season. Two to six dark spots present along the mid-line.
Remnants of juvenile banding may be present. Dorsal, caudal fins
with bright pink and white margins and faint yellowish to white
banding. Males may have shimmering white spots on dorsal fin.
Eyes are deep red.
Adults can undergo rapid colour pattern changes during territorial
and courtship displays.
Colour pattern changes in Tilapia mariae .
Baldaccini (1973) found that, during encounters between territorial
fish (males and females) T. mariae exhibited at least nine changes in
colour pattern, which included three major patterns and six
combinations of these patterns (see photos).
Pest fish profiles - Tilapia mariae – Photos
Adult:
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Appearance
Colour varieties (Baldaccini 1973):
A. Barred General colour of body and fins uniformly white-grey
B. Spotted Body yellowish, sometimes with golden or pale green
flecks
Unpaired fins light coloured with some pale-blue
spots
Lower margins of ventral pelvic and anal fins black
Small irregular black spot between bases of pelvic fins
C. Dark
Tilapia-mark and dark opercular spot well-visible
Body and fins dark, greyish-black, except for white
upper margin of dorsal fin
Eye is dark like the body and no ocular band present
D. Neutral Body colour yellowish and fins transparent
E. Falsebarred
No markings except for opercular spot
Body is greyish, dorsally darker than ventrally
Black mark visible at base of pectoral fins
F. Green
G. Olivegreen
Fins are dark, partially hiding Tilapia-mark and black
margins of ventral and anal fins
Body and fins are green or greyish-green
Body and fins are olive-green darkening dorsally
Eye is neutral (black pupil plus white ring) or dark
without band
Opercular spot v. light and edge of gill cover is bright
green
H. Spotted- Similar colour to B with incomplete vertical bars less
barred
well developed caudally
I. CrossSimilar colour to B.
barred
Lateral spots appear as a dark longitudinal band
A second faint broken band of smaller spots present
between lateral band and dorsal fin base
These colour patterns were associated with different behaviours:
the spotted pattern, indicative of territorial fish, is correlated with
high levels of aggressive and courtship behaviour, while the barred
pattern is correlated with submissive or escape behaviour This
pattern is usually displayed by juveniles and females when entering
a male's territory and may stimulate tendencies incompatible with
attack (e.g. parental or sexual tendencies) (Baldaccini 1973; Slovin
and Rowland 1978).
Size
Maximum size: 30-40cm total length (TL), but can mature and
reproduce at smaller sizes (9-18cm TL).
Distribution
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World distribution:
Figure 1: Natural and introduced range of Spotted tilapia.
Native Range
Tilapia mariae occurs in fresh and brackish waters of the lower
forested reaches of river systems and coastal lagoons from southern
Cameroon to the Ivory Coast (approx. 2N to 6N lat.), including
Benin, Ghana and Nigeria, in western equatorial Africa. The
species also occurs in highland volcanic crater lakes (Barombi
Mbo, Kotto and Mboandang) and the inflowing Mungo and
Meme river systems of the Mt. Cameroon complex in West
Cameroon.
3.2% of the total drainage area for the North East Drainage
Division, and, excluding the Victorian population, represents a
more restricted distribution compared with that of the
Mozambique tilapia. Besides its occurrence in central and southeast Queensland and Western Australia, O. mossambicus occupies
seven catchments in northern Queensland which represent about
73% of the total North East Drainage Division (Table 1). Both
species co-occur in only one catchment: the Barron River system.
Table 1: River catchments in northern Queensland in which the
Mozambique tilapia and Spotted tilapia occur.
River system
Catchment O.
T. mariae
Area (km²) mossambicus
Endeavour
2200
v
Barron
2175
v
v
Mulgrave-Russell
2020
v
Johnstone (N & S)
2330
v
Herbert
10125
v
Black-Alice
1025
v
Ross
1815
v
Haughton
3650
v*
(Barrambush Ck.)
Burdekin
129860
v
Introduced Range
T. mariae has been introduced into three countries: the former
USSR for warm water aquaculture, the USA and Australia for the
aquarium trade. The species has established feral populations in
the latter two countries only, in California, Nevada and Florida
(USA), and in Victoria and Queensland (Australia). The species is
now present in three catchments in northern Queensland: the
Barron River, the Mulgrave-Russell system and the North and
South Johnstone Rivers system.
Introduction into Australia
Tilapia mariae was first reported in 1980, along with two other
cichlid species in cooling ponds of a power station at Morwell,
Victoria. The species was first reported in Queensland from the
lower Barron River near Kamerunga Bridge, Cairns, although the
timing of this introduction was not known. In 1990 the species was
reported also occurring in creeks between Kewarra Beach and
Palm Cove to the north of Cairns, and in 1994 in the lower reaches
of Freshwater Creek which flows into the Barron River near
Kamerunga. The species was collected from weirs on Kenney
Creek which flows into the Upper Barron River above Lake
Tinaroo, Atherton Tablelands, although it is possible the species
was present in the mid 1980s in Kenney Creek or in a feeder stream
(Leslie Creek) or nearby impoundments along with the
Mozambique tilapia, O. mossambicus.
In 1993, the species was reported from two sites in the South
Johnstone River and subsequently in 1996 from the Russell and
Mulgrave Rivers, and the North Johnstone River in 1999, and is
now widely dispersed and abundant in both the freshwater and
estuarine sections of these catchments. These catchments are about
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Diet, Reproduction, Ecological Tolerances & Impacts
space with native or other introduced fish species (e.g., O.
mossambicus) where they co-occur in northern Queensland.
Anecdotal evidence, however, suggests that the species, since its
introduction in the Upper Barron River catchment, is increasingly
a dominant component of the fish community in Lake Tinaroo,
Atherton Tablelands.
Diet
Tilapia mariae is primarily a planktivore (feeding on unicell algae),
but is an opportunistic feeder on filamentous alagae, cyanobacteria
(blue-greens), detritus, leafy aquatic plants, invertebrates and fish
eggs. The species has numerous, fine teeth with moveable slender
shafts adapted for rasping and grinding. It has numerous gill rakers
for sifting small food particles and has a long gut (x2.9 its body
length) which is characteristic of a herbivorous (plant) or plankton
feeder.
Reproduction
T. mariae is a biparental substrate spawner and nest guarder. The
species is monogamous, although males have been observed
mating with more than one female. Males and females establish
breeding territories singly or as a pair. Single ripe females will visit
males when ready to spawn.
The number of eggs produced during a breeding season depends
on the size of the female and can vary between about 300 and 6000
adhesive eggs that are laid on a cleared hard substrate, such as
rocks, wood, and leaves of aquatic plants and then fertilised by the
male.
Spawning in the native (equatorial) range is year-round with peaks
in early and late summer. In northern Queensland breeding is
probably aseasonal with peak activity during the Wet Season. Both
parents will aggressively defend eggs and juveniles from intruders
in their territory and continue protection until juveniles are freeswimming and have developed their barred patterning at about 34cm total length.
The species also exhibits lunar periodicity in spawning so that
more egg batches are laid before the full moon. This may
synchronise reproductive behaviour of mating pairs and enhance
parental care at night in early stages of egg and fry development.
Also, decreasing moonlight in the next lunar phase may reduce
visibility of young to nocturnal predators until they develop the
more cryptic (barred) coloration.
Ecological tolerances
There is limited published information on the physiological
tolerances of T. mariae. The species is eurythermal with upper and
lower lethal temperatures of 37°C and 11°C respectively, and a
preffered temperature range of 25-33°C (Siemien and Stauffer
1989).
Ecological impacts
In Florida, T. mariae was observed being extremely aggressive
towards other exotic fishes. The species' complex and aggressive
bi-parental care may provide a selective advantage and may have
been a crucial factor in its ability to rapidly spread and dominate
freshwater communities previously dominated by native, uniparental centrarchids. While the species is predominantly
herbivorous, there is evidence, although at relatively low levels and
infrequent, of piscivory (eating fish eggs and even cannibalism).
There have been no behavioural or trophic studies of T. mariae
including predator-prey interactions and competition for food and
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Glossary
Anal
Caudal
Dorsal
Exotic
Eurythermal
Fry
Herbivorous
Lateral
Longitudinal
(Fin) beneath the body, behind anal opening
Towards the tail.
Situated near to or on the back
A species which has not lived in a particular region for
thousands of years, but has immigrated from another region,
usually within the past 250 years. The words "alien", "nonindigenous" and "non-native" are synonyms
Tolerating a wide range of temperature, opposite to
stenothermal
Newly hatched or born fish
Plant eating
Situated at or extending to the side
Running lengthwise
Ocular
Opercular
Pectoral
Pelvic
Piscivory
Planktivore
Stenothermal
Trophic
Ventrally
Situated near or related to the eye
Situated near or related to the gill cover
Situated near the chest, or lower front of the fish
Related to the pelvis, or lower middle of the fish.
Fish-eating or fish-egg-eating
Animal feeding on plankton: tiny plants and animals that float or
drift near the surface of a body of water
It can tolerate a limited range of temperatures, opposite to
eurythermal
Related to food and nutrition, or position in a food web
Towards the belly or underside of the body, the opposite of
dorsal
References
Baldaccini, N.E. (1973). An ethological study of reproductive behaviour including the colour patterns of the cichlid fish Tilapia mariae/(Boulanger). Monitore Zool. Ital. 7: 247-290.
Siemien, M.J. and Stauffer, J.R., Jr., 1989. Temperature preference and tolerance of the spotted tilapia and Rio Grande cichlid. Archiv fuer Hydrobiologie 115(2): 287-303.
Slovin M. and Rowland W.J., 1978. The effects of color patterns on the aggressive behavior of Tilapia mariae (Boulenger). Behav. Biol. 24:378-386.
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Created by A. Webb, M. Maughan and Matthew Knott
© ACTFR, James Cook University, 2007
For further information please contact TropWATER@jcu.edu.au, tel: 07 4781 4262
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Other information sheets available:
Mozambique tilapia – Oreochromis mossambicus
Oscar – Astronotus ocellatus
Burton’s haplochromis – Haplochromis burtoni
Mosquitofish – Gambusia holbrooki
Guppy – Poecilia reticulates
Swordtail – Xiphophorus helleri
Platy – Xiphophorus maculates
Three-spotted gourami – Thrichogaster trichopterus
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